Packaging bag

ABSTRACT

A tetrahedron-shaped packaging bag made of a flexible film material and comprising in the region of a tetrahedron corner of the bag, a pouring part which protrudes from the bag in an essentially tubular manner and which is closed on the free end thereof. The opening cross-section in the region of the transition between the bag and the pouring part is stabilized by a reinforcement in the film material of the bag, said reinforcement extending in a manner transversal to the pouring direction (y) opposite the tetrahedron corner.

The invention relates to a tetrahedral packaging bag made of a flexible film material, which, in the region of a tetrahedron corner of the bag, forms a discharge part which projects from the bag, is substantially tubular and closed at its free end.

Tetrahedral packaging bags made of plastics material-coated cardboard for drinks are known. To remove the drink, the packaging bag is provided at one point, for example, with an opening, which is closed by a film which can be pierced by a drinking straw. Other bags may be torn open to form a discharge along a peroration line. Furthermore, tetrahedral packaging bags made of a flexible film material for chocolate sweets filled with a sugar paste are known. As in many bag packagings, a tearing notch which is arranged in a sealing seam is used for opening.

A tetrahedral packaging bag made from a flexible film material, which, in the region of a tetrahedron corner of the bag, forms a discharge part which projects from the bag, is substantially tubular and closed at its free end, is known from EP-A-1 547 935. A substantial disadvantage of this bag is that the bag walls collapse or fold together in the region of the discharge part and thus constrict the discharge part or even close it and therefore strongly impede, in particular, the discharge of liquid and pourable bulk materials.

The invention is based on the object of providing a packaging bag of the type mentioned at the outset, with which liquid and pourable solid ingredients can be removed in a metered manner by way of a defined opening.

In the packaging bag, the solution according to the invention is achieved in that the opening cross section in the region of the transition from the bag into the discharge part is stabilised by a reinforcing element in the film material of the bag, which extends transverse to a discharge direction pointing away from the tetrahedron corner.

The reinforcing element is preferably formed by a folded seam consisting of the film material and projecting from a tetrahedron face of the bag, the folded seam expediently being formed by sealing the film material to itself.

The reinforcing element may also be formed by a rib, which is applied to the film material, made of a plastics material, such as, for example an adhesive or hotmelt. Further possibilities are, for example, a reinforcing embossing or a reinforcing material application of, for example, a printing ink.

The reinforcing element preferably has a substantially linear course. The reinforcing element may have a straight or curved course. The reinforcing element may also be constructed from substantially point-shaped elements.

The tubular discharge part preferably has a partial sealing seam extending substantially parallel to the discharge direction and passing in the region of the tetrahedron corner of the bag into a sealing seam of the bag, and the reinforcing element runs in a tetrahedron face opposing the sealing seams.

The discharge part expediently has at least one tearing notch extending transverse to the discharge direction. The tearing notch may pass into a weakening line running round the discharge part.

The discharge part can expediently be folded or tilted and preferably fixed by means of an adhesive on the bag in the folded-over or tilted position. The discharge part may also be fixed to the bag and reclosed in the folded-over or tilted position by means of a strip, which is glued or sealed in between the bag wall and discharge part, with an integrated permanent adhesive layer.

The discharge part projecting according to the invention from a tetrahedron corner of the bag may, for example, be folded back against one of the bag faces when the packaging bag is unopened, and fixed in the folded-over position by means of an adhesive arranged on the bag face or on the discharge part. During transportation and storage of the packaging bag, the discharge part is thus relatively well protected against mechanical damage. Once the packaging bag has been opened by severing the discharge part in the region of its free end, by suitable arrangement of the adhesive in conjunction with the capacity of the discharge part to fold or tilt, a simple possibility is produced for reclosing the opened bag. At least in the case of pourable, solid bulk materials, the filling product can be effectively prevented from escaping when the packaging is tipped over with this simple closure.

The discharge part may also be formed by sealing regions into a narrowed discharge channel, optionally with a valve action.

The discharge part may be narrowed by sealing regions into a through-opening with a valve action. The through-opening is preferably configured as a slot, which can be widened when pressure is exerted on the bag by the filling product and which automatically closes without pressure.

The preferred filling products for the packaging container according to the invention include drinks of all types and pourable solids such as, for example, maize, semolina and granular food of this type as well as washing powder.

Further advantages, features and details of the invention emerge from the following description of preferred embodiments and with the aid of the drawings, which are merely used for illustration and are not to be interpreted in a restrictive manner. In the drawings, schematically:

FIG. 1 shows the continuous production of packaging bags as tubular bags with a longitudinal sealing seam;

FIG. 2 shows an enlarged detail of FIG. 1;

FIG. 3 shows the plan view of a packaging bag produced by the method according to FIG. 1;

FIG. 4 shows the side view of the packaging bag of FIG. 3 in the viewing direction X;

FIG. 5 shows the view of the lower side of the packaging bag of FIG. 3;

FIG. 6 shows the side view of a discharge part with a valve action;

FIG. 7 shows the side view of a folded-over discharge part;

FIG. 8 shows a section through the folded-over discharge part of FIG. 7 along the line I-I.

According to FIG. 1, a film strip 32 which is provided to produce tetrahedral packaging bags 10 is unrolled from a supply roll 34 and continuously formed in a known manner with the formation of a longitudinal sealing seam 12 into a tube 13 in a device which is not shown in more detail. After the provision of a first transverse sealing seam 14, the filling product can be poured in in the arrow direction A. Although the film tube 13 runs in the horizontal direction in the drawing, it is readily understandable for the tube to be guided vertically when liquid or pourable filling products are poured in. After each filling operation with the filling product, apart from the continuously formed longitudinal sealing seam 12, a second transverse sealing seam 16 closing the packaging container is also provided, in each case, respective consecutive transverse sealing seams 14, 16 being arranged rotated through an angle of 90° with respect to one another, forming a tetrahedron.

During the production of packaging bags 10, shown in FIG. 1, as shown in detail in FIG. 2, one of the transverse sealing seams, in each case, is placed in such a way that a discharge part 20 is produced in the region of one of the formed tetrahedron corners 18. The second transverse sealing seam 16 which is located in the plane of the longitudinal sealing seam 12 initially extends in a first partial region 16 a corresponding to the desired tetrahedron shape. A first seam region 16 a extends in the region of the container corner 18 in the discharge direction y of the discharge part 20, which is thus formed in a tubular manner. A second partial region 16 b of the second transverse sealing seam 16 extends substantially parallel to the original seam direction and is used to close the discharge part 20 tapering here at the free end 22 thereof.

In the present production example, the discharge parts 20, 20′ of two consecutive packaging bags 10, 10′ are in each case directed toward one another and, between the corresponding transverse sealing seams 16, 16′, a film portion 17 is produced, which, once the two packaging bags 10, 10′ have been separated along a separation line s, is discarded. Obviously, other mutual arrangements of the discharge parts of two consecutive packaging bags are also possible during the production of the tubular bags.

The packaging bags 10 which are formed between consecutive transverse sealing seams 14, 16 are separated in a cutting device, not shown. An individual packaging bag 10 is shown in FIGS. 3 to 5.

It can be seen from FIGS. 4 and 5 that a folded seam 30 which is formed in the film material of the bag 10 extends in the region of the transition from the bag 10 into the discharge part 20 transverse to the discharge direction y pointing away from the tetrahedron corner 18. This folded seam 30 is produced in that film material is sealed against itself, forming a sealing seam. The opening cross section in the region of the transition from the bag 10 into the discharge part 20 is stabilised by this reinforcement. The folded seam 30 is arranged in a tetrahedron face 36, which extends, as part of the tubular discharge part 20, substantially parallel to the discharge direction y, and opposes the second transverse sealing seam 16 and the partial sealing seam 16 a.

As shown in FIG. 5, a diaphragm valve 37 is sealed in the tetrahedron face 36. A diaphragm valve 37 of this type may, for example, be necessary if the bag 10 is used as packaging for coffee present in the form of beans or in ground form. In this case, a gas pressure building up in the interior of the bag is counteracted in that gases can escape to the outside. On the other hand, the diaphragm valve 37 prevents a passage of gas, for example of oxygen, from the outside to the inside. The diaphragm valve 37 is sealed, for example before the formation of a tube, at a predetermined point on the film strip 32 (FIG. 1).

In the example shown in FIGS. 4 and 5, the folded seam 30 runs in a straight line on the outside of the bag. A folded seam 30′ with a curved course is shown by dashed lines. The course of the folded seam 30, 30′ may, however, have any desired form and depends on the product to be filled. The folded seam 30, 30′ may also be provided on the inside of the bag 10. A further possibility is to press film material with a tool from the outside to the inside and to seal it as an inwardly directed folded seam.

Instead of a folded seam 30, 30′ it is, for example, also possible to apply a rib made of plastics material as a reinforcing element in molten form to the outside or inside of the bag 10. The material used for the rib may, for example, be an adhesive or a hotmelt. Further possibilities for local reinforcement are produced, for example with an embossing or by the use of a reinforcing printing dye.

The reinforcing element in the form of a folded seam 30, 30′ or a plastics material rib arranged with a corresponding course is preferably provided simultaneously with the production of the bag.

For better metering of liquid and viscous filling products, a through-opening 42 with a type of valve action may be arranged in the discharge part according to FIG.

6 by the provision of additional sealing regions 38, 40. The sealing regions 38, 40 are, for example, arranged in such a way that a slot is produced as the through-opening 42, which is firstly opened by pressure on the bag and allows filling product through. When the pressure is removed, the slot closes automatically and prevents filling product from escaping.

In order to avoid mechanical damage to the discharge part 20 during transportation and storage and to prevent unintentional escape of filling product when the bag is opened, the discharge part 20 may be tilted or folded over about an axis e transverse to the discharge direction y. To fix the folded-over discharge part 20 to the bag (indicated by dashed lines in FIG. 4), an adhesive 28 is provided, which is arranged in the present example in the form of an adhesive strip on the discharge part 20.

As shown in FIGS. 7 and 8, instead of an adhesive 28 applied to the bag wall or to the discharge part 20, a strip 50 with an integrated permanent adhesive layer 44 may also be glued or sealed in between the turned-over discharge part 20 and bag wall 49. The strip 50, for example, consists of two outer layers 46, 48 made of a polyolefin, such as polyethylene, with the permanent adhesive layer 44, which is arranged between the two outer layers 46, 48 and may consist, for example, of a hotmelt. The bag 10 can thus be made reclosable by a simple material selection. 

1. A tetrahedral packaging bag made of a flexible film material, which, in the region of a tetrahedron corner of the bag, forms a discharge part which projects from the bag, is substantially tubular and having a free end which is closed, wherein the opening cross section in the region of the transition from the bag into the discharge part is stabilised by a reinforcing element in the film material of the bag, which extends transverse to a discharge direction (y) pointing away from the tetrahedron corner.
 2. A packaging bag according to claim 1, wherein the reinforcing element is formed by a folded seam consisting of the film material and projecting from a tetrahedron face of the bag.
 3. A packaging bag according to claim 2, wherein the folded seam is formed by sealing the film material against itself.
 4. A packaging bag according to claim 1, wherein the reinforcing element is formed by a rib, which is applied to the film material and made of a plastics material.
 5. A packaging bag according to claim 1, wherein the reinforcing element has a substantially linear course.
 6. A packaging bag according to claim 1, wherein the reinforcing element has substantially point-shaped elements.
 7. A packaging bag according to claim 1, wherein the tubular discharge part has a partial sealing seam extending substantially parallel to the discharge direction (y) and passing, in the region of the tetrahedron corner of the bag, into a sealing seam of the bag, and the reinforcement extends in a tetrahedron face opposing the sealing seams.
 8. A packaging bag according to claim 1, wherein the discharge part has at least one tearing notch extending transverse to the discharge direction (y).
 9. A packaging bag according to claim 8, wherein the tearing notch passes into a weakening line running around the discharge part.
 10. A packaging bag according to claim 1, wherein the discharge part can be folded or tilted and preferably fixed to the bag in the folded-over or tilted position and reclosed by means of an adhesive or by means of a strip, which is glued or sealed in between the bag wall and discharge part, with an integrated permanent adhesive layer.
 11. A packaging bag according to claim 1, wherein the discharge part is narrowed by sealing regions to form a through-opening with a valve action.
 12. A packaging bag according to claim 11, wherein the through-opening is configured as a slot which widens when pressure is exerted on the bag by a filling product and automatically closes in the absence of pressure.
 13. A packaging bag according to claim 1, wherein the discharge part is folded back against a face of the packaging bag when the packaging bag is unopened.
 14. A packaging bag according to claim 1, wherein the discharge part is fixed in a folded-over position against a face of the packaging bag when the packaging bag is unopened by means of an adhesive.
 15. A packaging bag according to claim 1, in combination with a filling product.
 16. A packaging bag according to claim 1, wherein the reinforcing element is formed by embossing or by the use of a reinforcing printing dye. 